Part of the M25 will be closed for the rest of the day after a lorry overturned, leaving on person in a critical condition while another is being treated for serious injuries.

A stretch of road shut is between junction 23 at South Mimms and junction 25. Credit: Bruno Fernandes. Twitter: @nbrunofernandes

The M25 is closed between J23 (St Albans Road) and J25 (Enfield). Congestion was reported earlier on the clockwise Clockwise to J22 with the A1081 (St Albans / London Colney) and on the anticlockwise section to J27 with the M11.

The emergency services are still on the scene but two air ambulances called to the scene have now left.

Motorists faced severe delays on the M25 after police were forced to close the Dartford Crossing in both directions due to a security alert.

Drivers were caught in nine-mile long tailbacks after both the QE2 Bridge and Dartford Tunnels were closed for almost seven hours during rush-hour traffic last night, as bomb disposal experts investigated a suspicious item.

Officers had been called to the crossing at 4pm following a report of a male pedestrian behaving unusually, Kent Police said.